Surgery-Rigged pulley helps patients

According to Dr. John Poll, curing a laborious birth defect that left Alyssa Parente a sunken nose and hugely bulging eyes, sliced apart all the bones of her face but didn't re-join them before sewing her up. Instead, 10-year-old Alyssa got a promising alternative to grueling bone grafts: Poll attached a pulley-like contraption to her facial bones that her parents tightened each day with a screwdriver, slowly pulling out the sunken bones so they could grow into the right position.

Two months later, Alyssa had a normal face. According to Polley, they are letting the body do its own bone-grafting, who pioneered the technique with a colleague at Chicago's Rush Craniofacial Center.

About 3,000 children a year are born with severe craniofacial defects such as Apert's syndrome, which struck Alyssa, and similar disorders. Their bones fuse together abnormally so the head and face can't grow, leaving sunken faces and misaligned jaws. It's not just a problem of appearance. Often, the malformed head causes problems with eating, breathing, hearing and vision.

Standard reconstruction involves multiple surgeries to cut apart most of the face bones, move them up, down or forward, and then hold them in the new spot with grafts from hip or rib bones. Some children have such little bone to work with that they can't complete such surgery until they're teen-agers. And if the graft is poorly placed, it can't be moved.

Enter Poll's alternative. It sounds traumatic. After all, Alyssa ran around for weeks last summer with all the bones in her face broken. Indeed, Poll's experience with a few dozen patients suggests this so-called ``rigid external distraction'' can be easier than standard surgery, is done at younger ages, and lets the doctor gently push and pull until the child's face looks just right.

The procedure is still experimental, cautions Dr. Harold Slavkin of the University of Southern California, the National Institutes of Health's former chief of dental and craniofacial research. But it has ``enormous promise,'' he says - so much that some scientists are studying how to pair this grow-your-own-new-bone method with genetically engineered drugs to make that bone grow faster.

Surgeons have long lengthened leg bones by breaking them, pulling them apart and letting the body grow new bone - just as it would if you'd naturally broken your leg. Several years ago, a New York physician adapted that technique, called distraction osteogenesis, to fix malformed jaws.

If it worked on single bones, Poll reasoned, why not for children's entire faces. First, Polley operates to cut all the stunted, sunken facial bones, but he doesn't move them. Instead, he attaches wires to the skull or certain other bones. Those wires screw into to a halo-like device, designed with Rush dentist Alvaro Figueroa, worn in front of the face.

With a turn of a screwdriver twice a day, parents tighten the wires. That tightening moves the pieces of bone forward a millimeter a day. As that happens, the body manufactures new bone to fill the gap. Over six weeks, facial bones can be extended as much as the length of a paper clip.

Poll doesn't have long-term data yet proving the children will never need additional surgery. But the technique already is widely used for easier cleft palate repair, and Poll says only 5 percent of those patients relapse, fewer than with traditional surgical cleft repair.